This invention relates to a two cycle engine and more particularly to an improved arrangement for assisting in the starting of two cycle engines.
As is well know, two cycle engines are normally lubricated by introducing lubricant to the engine at least in part through its induction system, particularly when the engine is of the crankcase compression type. The lubricant is circulated through the engine along with the intake charge and this lubricant may be either supplied as mixed with the fuel or from a separate lubricating system. Although this type of system is extremely effective, there are some disadvantages.
Specifically, when the engine is shut off, there will be some lubricant that remains on the wall of the cylinder. Although this is desirable to insure adequate lubrication upon restarting, if the engine temperature is high at the time the engine is shut off or becomes elevated after it shuts off, the lubricant may be partially carbonized. In addition, if this does not occur, the lubricant may become mixed with combustion products that also remain on the cylinder walls and the viscosity of the lubricant can increase.
If such increased viscosity lubricant remains on the cylinder walls and the engine is next started, the increased viscosity of the lubricant will give rise to high cranking loads and result in low cranking speeds. This is obviously undesirable.
It is, therefore, a principal object to this invention to provide an improved system for facilitating the starting of a two cycle engine.
It is a further object to this invention to provide an arrangement for facilitating the starting of an engine if lubricant remaining on the cylinder walls will have attained a higher than desired viscosity.
It is a further object to this invention to provide an improved arrangement which will reduce the viscosity of lubricant on the cylinder walls during starting after periods of inactivity and if the temperature is below a predetermined amount.